Conventionally, a sheet-like fiber structure including inorganic substances such as silicon dioxide and glass, and organic materials such as cellulose, polypropylene and polyamide is used as a heat insulation material or a voltage resistance material.
Electrolytic capacitors, storage batteries, and the like, have a voltage resistance material called a separator, which is disposed together with an electrolytic solution between a positive electrode and a negative electrode. While the separator prevents a short circuit between the electrodes, it allows ions or electrons existing in the electrolytic solution to permeate thereinto.
Recently, however, storage batteries and the like have had a higher capacity and a higher power. Accordingly, it is necessary to reduce a distance between electrodes as much as possible and, to secure voltage resistance characteristics and liquid permeability. Furthermore, when a short circuit accidentally occurs because foreign matters exist between the electrodes, heat is generated in the vicinity of a place in which the short circuit occurs. As a result, a separator may be damaged due to a high temperature.
Furthermore, a composite of a polymer material and an inorganic material is used as a culture dish material to be used during cell culture. The composite is formed by filling or laminating the inorganic material such as silicon dioxide to the polymer material such as an olefin polymer and a polyester resin. Herein, it is preferable to use polymer materials, which are formed in a form of a porous shape, a tubular shape, a hollow fiber shape, and the like.
In a structure to be used as a culture dish during cell culture, a scaffold to which cells are attached may be disposed such that the cell culture is carried out efficiently. The scaffold supplies sufficient nutrient and, if necessary, carbon dioxide gas, air, and the like, to a group of cells that are being cultured.
The scaffold to be used for a cell culture dish is required to have liquid permeability and air permeability because it needs to supply sufficient nutrient and gas to a group of cells. Furthermore, when the scaffold is subjected to surface treatment, heat treatment or chemical treatment is required to be carried out. Therefore, the scaffold is required to have heat resistance and chemical resistance.
Note here that as prior art literatures regarding the invention, the following Patent Literatures are known.